Weather Alert

Weather advisory

Date: 8 January 2019

Area’s affected:

KZN

Eastern Cape

Western Cape

Limpopo

Mpumalanga

Gauteng

Free State

North West Province

Northern Cape

Period: 7 January until 13 January 2019

Tuesday, mild conditions and isolated showers or thunderstorms can be expected on the highveld anywhere north and west of a line, Vryburg to Bloemfontein to Newcastle to Nelspruit to Polokwane. Within this area, scattered and potentially energetic thunderstorms may develop over E parts of the North West and perhaps the extreme W of Gauteng today and over E parts of the North West, N parts of the Free State and the extreme S of Gauteng on Tuesday.

On Tuesday, a moist E to SE airflow will begin to develop over the Eastern Cape coast which will lead to cloudy conditions and the chance of some light rain. Over the NE interior of the province and also western and central parts of KZN, increased moisture levels will lead to the chance of isolated to scattered thunderstorms developing.

On Wednesday and Thursday, thunderstorms become far less likely over W parts of the highveld but isolated to scattered showers or thunderstorms can be expected over the majority of the Eastern Cape, E and central parts of the highveld, W and central parts of the KZN and thunderstorms will also spread into parts of the lowveld. Over W parts of KZN and the far S of Mpumalanga, energetic thunderstorms may develop.

On Thursday, a cold front is expected to affect the Western Cape and although not a lot of rain is expected, the air behind the front will be quite cold for the time of the year and winds will be fresh. On Friday the front will push into the Eastern Cape and should clear any thunderstorm risk from the province by later in the day. Elsewhere on Friday, scattered thunderstorms are expected to persist over NE parts of the country (including KZN).

Over the weekend, scattered showers and thunderstorms are expected to persist over KZN with thunderstorms becoming more isolated and less likely over the highveld. Although fine conditions are expected over western and southern areas, conditions will remain mild for the time of year due to W or SW winds.

Storms containing large hail: (any mention of thunderstorms in the forecast automatically presumes a very low chance of hailstorms). Medium chance on Monday over E parts of the North West and perhaps the extreme W of Gauteng. Medium chance on Tuesday over E parts of the North West, N parts of the Free State and the extreme S of Gauteng. Medium chance on Wednesday and Thursday over W parts of KZN and S parts of Mpumalanga.

Intense lightning: (any mention of thunderstorms in the forecast automatically presumes a low chance of intense lightning). Medium chance on Monday over E parts of the North West and perhaps the extreme W of Gauteng. Medium chance on Tuesday over E parts of the North West, N parts of the Free State and the extreme S of Gauteng. Medium chance on Wednesday and Thursday over W parts of KZN and S parts of Mpumalanga.

Flash flooding: (any mention of thunderstorms in the forecast automatically presumes a very low chance of flash flooding). Low chance on Monday over E parts of the North West and perhaps the extreme W of Gauteng. Low chance on Tuesday over E parts of the North West, N parts of the Free State and the extreme S of Gauteng. Low to medium chance on Wednesday and Thursday over W parts of KZN and S parts of Mpumalanga. Medium chance on Friday to Sunday over KZN.